2001-01-29_INSPECTION - M1977493

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MINE ID # OR PROSPECTING ID #: M- 1977 -493 PAGE: 2 INSPECTION DATE: 9 -26 -00 INSPECTOR'S INITIALS: ACS OBSERVATIONS This inspection was conducted in response to the Operator's request for surety reduction based on completion of reclamation tasks required under the approved reclamation plan for the Climax mine. The surety reduction request was submitted by Climax in accordance with Rule 4.13 of the Hard Rock /Metal Mining Rules and Regulations of the Mined Land Reclamation Board and is being processed by the Division of Minerals and Geology (DMG) as revision SR -03 to Permit No. M -1977 -493. For clarification, the previous surety reduction revisions for this permit, numbered SR -01 and SR -02, are described here: Revision SR -01: Removal of Clinton Reservoir from the reclamation permit area, approved October 5, 1992. Revision SR -02: Conditional acceptance that the approved post- mining land use of developed water resources had been achieved for Eagle Park Reservoir, conditional approval issued August 26, 1998. Please note that revision SR -01 was not associated with permit amendment AM -02 (the 1989 amendment) and that SR -02 was likewise not associated with amendment AM -03, as was suggested in the SR -03 application from Climax. The 7 -shaft location was inspected. This is a ventilation shaft that is located at the northeast perimeter of the Storke Complex and just below the Leadville, Colorado and Southern Railroad grade. The Fan House and Compressor Buildings have been demolished and removed. Foundation reclamation is in progress and has included concrete drilling and blasting. The foundations and elevated concrete structures such as equipment pedestals and stem walls will be managed for reclamation through combinations of rubblization, removal, backfilling into cuts and burial either in place or in other suitable locations. The 7 -shaft opening was sealed in 1996. 7 -shaft is a circular 28 -foot diameter concrete lined opening. The shaft seal design is for a cast -in -place concrete slab. The design includes bottom forms for the slab that are bridge decking supported by wide flange beams on 4 foot centers. The cast - in -place slab was designed in general accordance with concrete slab designation "I" described on Standard Drawing No. 3 in "General Bid Specifications," Colorado Inactive Mine Reclamation Program (IMP), 1996. This slab design is suitable for spans up to 24 feet with up to 12 feet of fill thickness placed over the finished slab. Since the 7 -shaft span is 28 feet, no more than four feet of cover fill may be placed on the finished slab in accordance with the IMP specification. Four feet maximum cover fill will be made one condition of the DMG's acceptance of the slab that has been installed. Apparently, and as reported by Climax, the compressive strength of the cast -in -place concrete in the slab has never been tested. 4,000 psi concrete was specified. The 7 -shaft design also deviated from the IMP specifications where the two central wide flange beams extend slightly more than one foot onto the shaft collar concrete rather than the specified two -foot minimum. The 7 -shaft design exceeded IMP specifications for slab designation "I" where a 22 inch slab thickness was employed compared to the 20 inch thickness that is specified and where the edges of the slab are doweled into the concrete shaft collar using 5 foot long #11 bars. The DMG cannot accept the 7 -shaft closure as a completed reclamation task for the purpose of determining the bond amount until the following listed items are addressed: